| Popis: |
Lossless image coding is a important research field for multimedia store and digital library. H.264 provides a better compression rate than the JPEG-LS based on intra prediction and entropy coding (CABAC and CAVLC). In this paper, we suggest that entropy coding should be adaptively adopted for various image content variations(ICV) to increase H.264-LS compression rate. The ICV is obtained by existing intra prediction residue values in our proposed method. In the meantime, we add the (5, 3) discrete wavelet transform (DWT) for higher ICV images after executing 4times4 intra prediction to increase H.264-LS compression rate again. Simulation results show that using the adaptive entropy coding has 97% correct rate and 8.7% compression rate improvement than used single entropy coding. If add the (5, 3) DWT filtering again, we can at least obtain 2.3% compression rate than the adaptive entropy coding. |
